Feeding Young Horses for Sound Development

B-5043
05-05
FeedingYoungHorses
forSoundDevelopment
FeedingYoungHorses
forSoundDevelopment
PeteG.Gibbs
ProfessorandExtensionHorseSpecialist
DepartmentOfAnimalScience
EquineSciencesProgram
TheTexasA&MUniversitySystem
GaryD.Potter
Professor
DepartmentOfAnimalScience
EquineSciencesProgram
TheTexasA&MUniversitySystem
Introduction
To a large extent, industry trends dictate methods used
to manage horses. Rapid growth and development often
is important for halter futurity contenders and for foals
entering race training as yearlings, and while size itself
is not a marketing factor for some disciplines such as
cutting and reining, rigors of early training place great
demands on young skeletal systems. Horse owners realize
that young horses’ marketing or performance potentials
often hinge on evidence of significant early development.
Even without the demands of marketing or competition,
sound early development is important for longevity and
usefulness for all types of foals. Horse owners should
decide whether to feed young horses for moderate or for
rapid growth (Fig. 1). Either growth rate allows mature
horses to grow as big as their genetic bases will allow.
However, rapidly growing horses reach their mature height
and weight much earlier than do those fed to produce
moderate growth rates.
Limited data from Texas horse-farm owners suggests
that they make a profit from 42 percent of their young
horses, while they break even on 20 percent and lose
money on 21 percent of them. The largest profit margin
appears to come from the 14 percent of young horses
that are sold.12 Although most evidence suggests that
horse owners cannot starve profit out of young horses
by scrimping on their nutrition, as many as 44 percent
of farms fail to meet known nutrient requirements for
young horses, particularly for weanlings.
Sound feeding management, including feeding a
balanced nutrient supply, is crucial to improving profit
through more marketable and useful horses. With such an
approach, problems may still emerge from time to time,
but sound early management can be expected to make a
difference in young horses’ development, regardless of
the animals’ intended purpose.
1185
Some young horses must achieve rapid early growth to be competitive.
DevelopmentalProblems
Bone and joint problems known as developmental
orthopedic diseases (DOD) are a major concern of horse
owners.29 DOD appears to be heritable.22 Horses with
genetic predispositions for large mature size often develop
skeletal problems regardless of how they are managed.
However, management may contribute to skeletal
problems, since nutrient imbalances and excessive forced
exercise of confined horses also apparently can lead to
DOD. 36
The frequency of DOD in horses genetically predisposed
to skeletal problems has led to the misconception that
horses fed to reach full growth at a young age will become
unsound, but the adage that young horses are being
grown too fast is not necessarily true. Two studies
involving over 1400 young horses showed no relationship
between rate of growth and incidence of developmental
problems.23,50 However, when young horses are managed
for rapid early growth, nutrition and exercise programs
require careful administration to ensure structural
soundness as horses mature.
Rapid growth
Body weight (pounds)
Moderate growth
985
785
585
385
0
Figure 1. Example growth curve for young horses
4
8
12
16
20
Age (months)
24
28
32
36
5
The DOD complex includes epiphysitis, osteochondrosis
and juvenile arthritis, among other disorders. 37 Common
DOD symptoms include enlargement and deformities of
ankles, knees and hocks, as well as contracted tendons
(“pulling up”) in the pasterns. Although bone radiographs
indicate skeletal irregularities in many young horses,31
some horses never develop visible signs of DOD; others
have appearance or lameness problems interfering with
growth and performance. Some such problems are
developmental, while others are acquired as growth
progresses.37
To help prevent or minimize skeletal problems, diets
for young horses should be formulated carefully to contain
an adequate supply of major nutrients (Table 1) important
for promoting growth.31 Nutrients such as protein, calcium,
phosphorus and other minerals and vitamins must be
provided in correct amounts relative to each other and
must be in balance with the amounts of energy (“fuel”) a
horse eats. Inadequate concentrations of protein, minerals
and vitamins relative to energy concentration may cause
DOD in young horses. Protein quality, which means amino
acid profile, is more important than total protein for growth
promotion.32
Deficiencies in certain trace minerals may contribute
to DOD.8,29 The trace mineral needs of growing horses
are not completely known; young horses should be fed
concentrate feeds that contain adequate, balanced amounts
of trace minerals and salt. High-quality commercial feeds
usually contain adequate trace minerals, but horse owners
who prepare their own feed mixes will need to add
trace mineral salt or vitamin/trace mineral premixes to
concentrate diets.
Although other factors may have been involved in
growth problems observed, a survey of 19 Ohio and
Kentucky breeding farms suggests that foals may require
more copper than previously recommended.25 In another
study, three levels of copper were fed to weanlings with no
effect on wither height or on bone density.47 More recently,
both veterinarians and owners have been cautioned that
copper intake has been overemphasized and that not
enough attention has been given to intake of adequate
energy and high-quality protein.7
Toxic amounts of zinc appear to interfere with copper
absorption, but varying copper:zinc ratios routinely seen
in normal diets do not interfere with copper absorption.10,54
Zinc:copper ratios of 4:1 or 5:1 are recommended for
young, growing horses.29,31
Growing horses fed high-energy diets with nutrient
imbalances may gain weight faster than their bones can
develop;34,38 such above-average weight gains may not
be compatible with optimal bone-mineral deposition.33,48
Although feeding unbalanced high-energy diets may
contribute to skeletal problems,16 research has not shown
that high-protein diets cause DOD.3 Instead, nutrient
imbalances, rather than high-energy diets, appear to cause
skeletal problems.2,18,43 Gains in height decrease when
weanlings and yearlings are fed diets low in protein,
calcium and phosphorus.14,34 Conversely, young horses gain
more height, weight and heart girth when fed high-energy
diets with suitable amounts of protein and minerals.35
Limiting dietary energy limits growth; available energy
enhances growth. However, horses fed for faster growth
have greater total requirements for protein, minerals and
other nutrients than horses fed for slower growth.31
Table 1. Daily nutrient requirements of growing horses (1,100 pounds mature weight) (Adapted from National Research Council, 1989.)
Class
Weanling(4months)
Weanling(6months)
Moderategrowth
Rapidgrowth
Yearling(12months)
Moderategrowth
Rapidgrowth
Longyearling(18months)
Notintraining
Intraining
*Based on Stephens et al., 2004.
6
Digestible
energy
(Mcals)
Crude
Lysine Calcium Phosphorus Magnesium
protein
(gms)
(gms)
(gms)
(gms)
(lbs.)
Vit.A
(IUs)
14.4
1.60
30
34
19
3.7
8,000
15.0
17.2
1.65
1.90
32
36
29
36
16
20
4.0
4.3
10,000
10,000
18.9
21.3
1.90
2.10
36
40
29
34
16
19
5.5
5.7
15,000
15,000
19.8
26.5
2.0
2.60
38
50
27
48*
15
27*
6.4
17.2*
18,000
18,000
CharacteristicsofParticular
FeedstuffsandPotentialProblems
Careful selection of high-quality feedstuffs and accurate
ration formulation ensures that a horse’s juvenile skeleton
adequately develops as its body weight increases, which
is extremely important when young horses are receiving
forced exercise. Horses being fitted and conditioned for
sales, futurities and pre-race training remodel bone in
response to work. Accurate ration formulation and feeding
can’t guarantee the absence of DOD but at least will
eliminate possible nutritional causes of such problems.
Balanced concentrates often are formulated from
energy feeds such as oats, corn, barley and, to some extent,
sorghum (milo). Any energy source used in horse feed
must be accompanied by sufficient high-quality protein and
by proper proportions of necessary vitamins and minerals.
In a practice called “cutting,” commercial feeds are mixed
with another cereal grain like oats or corn,15 altering the
nutrient:energy balance of the final diet. Cutting ultimately
can contribute to growth abnormalities. Horse owners also
should be aware that moldy-corn poisoning can kill horses.
Rations should be formulated only with high-quality corn,
and corn screenings should never be used. 40
Protein supplements such as soybean, cottonseed and
linseed meals may be used in formulated rations. However,
soybean meal’s higher lysine concentration provides better
growth rates than does cottonseed meal when both are fed
in equal amounts.28,39 Cottonseed meal can be used if at
least half of the total supplemental protein will come from
soybean meal or if synthetic amino acids will be used to
correct specific amino acid deficiencies.
Some feeds containing 14 percent crude protein
are well balanced for broodmares but do not contain
sufficient amino acids for foals and weanlings. For young
horses, lysine is the number one growth-limiting amino
acid. Lysine is more important than energy or protein in
terms of influence on body-weight-gain in weanlings.32
Many feed companies have added synthetic lysine,
knowing that some farms will feed the same feed to
both mares and foals. Horse owners should make sure
such feeds contain sufficient lysine and minerals before
providing them to foals or weanlings. High-quality
protein sources used in formulating 16 percent crude
protein feeds will supply sufficient lysine, as well as
threonine, the second limiting amino acid.17
Fats and oils can increase energy density of grain mixes.
Most commercial horse feeds contain approximately 3
percent natural fat (shown on the feed tag), and some
contain supplemental fat (for example, a feed tag indicating
8 percent fat means that approximately 5 percent fat has
been added). Topdressing fat or oil onto a balanced diet
dilutes total nutrient balance, so rations must be properly
balanced if fat or oil will be added.
High-quality grass or legume hays can meet horses’
roughage needs. However, horse owners should be alert
for mold or insects in hay. Even slightly moldy hay should
not be fed. Alfalfa hay can contain blister beetles, which
produce cantharidin, a compound highly toxic to horses.
Before purchasing alfalfa hay, horse owners should ask
hay producers whether steps were taken to avoid blister
beetles. Blister beetles can be found in other hays, but they
are found more often in alfalfa than in other roughage
sources.
Young foals nurse up to 70 times daily, indicating that they are well suited
to small meals.
Where foals are allowed to eat with their mothers, that feed must be balanced to meet the foal’s requirements, not the mare’s.
7
CreepFeedingFoals
Although broodmares can produce large amounts
of milk, its nutritional density declines over time. Thus,
energy received from mare’s milk may not meet the
requirements of foals 4 months old (or even younger).6
Soon after birth, nursing foals become interested in eating,
often consuming small amounts of feed from the mare’s
trough. However, foals have very different nutritional
requirements than do mares, so a “creep ration” should be
provided. Foals may gain 2.5 to 3 pounds daily, and owners
can use the right feed to take advantage of this early
growth potential.
Creep feed should be introduced slowly and usually
should be made available on a free-choice basis.31 Free
access to creep feed improves the likelihood that foals will
consume it in frequent small meals, similar to nursing. Such
feeding systems can be effective because young foals nurse
up to 70 times per day. Mare-proof creep feeders can be
constructed in pastures or corrals near areas where mares
normally congregate, providing easy access to encourage
foals to start eating a crop ration and to minimize injury.
Feeders should be checked daily to monitor amounts
eaten and to prevent feed from spoiling due to weather,
birds, rodents or other factors. Careful management will
be necessary, especially where several foals use the same
feeders. Sometimes one foal may dominate, consuming
large amounts of creep feed while preventing other foals
from entering the feeder.
Concentrations of protein, minerals and vitamins
needed in a good creep feed are influenced by the amount
of energy (calories) young foals will eat. Feed tags usually
do not indicate calories in a feed but do list percentage
of crude fiber and fat. Both fiber and fat indicate caloric
density and can be used to determine minimum amounts
of protein, lysine and minerals that should be in a feed.
Table 2 shows the percentage needed in concentrates that
do not contain supplemental fat. A grain mix with no
supplemental fat usually contains 3 to 3.5 percent fat, the
amount naturally occurring in most grains.
Feed tags will always show percentage of crude protein
but may or may not include percentage of lysine or of
minerals. To meet foals’ amino acid requirements with
a reasonable amount of daily feed, a 14 percent crude
protein feed that contains synthetic lysine should be
fed. (Horse owners should ask their feed retailer or call
manufacturers directly to obtain this information if it is not
included on the feed tag.) Creep feeds containing not less
than about 6 percent crude fiber and not more than about
3 percent fat usually should contain at least 16 percent
crude protein, .70 percent lysine, .80 percent calcium and
.50 percent phosphorus, yielding about 1400 kilocalories
of digestible energy per pound. Feeds with lesser amounts
of these nutrients make it hard for young horses to
consume enough protein (particularly lysine) and minerals
in reasonable amounts of daily feed.
Supplemental fat increases total energy density of a
grain mix. Therefore, at a given crude-fiber level, feeds
containing supplemental fat need higher percentages of
protein and minerals than do grain mixes or concentrates
containing no supplemental fat. Table 3 shows minimum
amounts of protein and minerals needed in grains of
varying crude fiber content, where 5 percent supplemental
fat has been added (8 to 8.5 percent total fat shown on the
tag).
Again, some top-quality broodmare feeds are well
balanced for mares but lack protein quality and calcium:
phosphorus ratios needed by foals. Relative to amount
of energy provided, such feeds often provide no more
than 90 percent of the lysine and 80 percent of the calcium
needed by foals. Young horses allowed to eat such feeds
may consume enough energy to gain weight but receive a
nutrient supply inadequate for proper growth and skeletal
development, often resulting in fat foals with improperly
developed musculoskeletal systems. Without creep feeding
a balanced foal ration, such situations may be avoided only
by feeding broodmares a grain mix that meets the foal’s
nutrient requirements. In most cases, creep feeding foals
in a separate feeder is more economical. Table 4 shows an
example creep ration for young foals.
Horse owners should avoid feeding programs that let
foals eat from both the mare’s trough and from a creep
feeder by elevating mares’ troughs so that foals cannot
reach them.
Table 2. Concentrations of protein and minerals needed in creep feeds of varying crude fiber levels with no supplemental fat (3.0 to 3.5 percent crude fat
shown on tag)
Iftagindicatesa
crudefatcontentof
3.0–3.5%
andacrudefiber
percentof
Thenthefollowingminimumsareneeded
Crude
Protein*
%
Lysine
%
Threonine
%
Calcium
(%)
Phosphorus
(%)
3-4
18
.75
.55
.85
.55
5-6
17
.72
.52
.78
.52
7-8
16
.70
.50
.70
.50
*A 14 percent crude-protein feed will meet the amino acid requirements of a foal only if that feed has been supplemented with synthetic lysine. Ask the
feed manufacturer before feeding a 14 percent crude protein feed to foals or weanlings.
8
Table 3. Concentrations of protein and minerals needed in creep feeds of varying crude fiber levels with 5 percent supplemental fat (8.0 to 8.5 percent
crude fat shown on tag)
Iftagindicatesa
crudefatcontentof
8-8.5%
andacrudefiber
percentof
Thenthefollowingminimumsareneeded
Crude
Protein*
Lysine
Threonine
%
3-4
%
19
%
.80
5-6
18
7-8
9-10
Calcium(%)
Phosphorus(%)
.60
.90
.55
.75
.55
.85
.55
17
.72
.52
.78
.52
16
.70
.50
.70
.50
*A 14 percent crude protein feed will not contain sufficient lysine to provide the protein quality needed by foals, unless the feed manufacturer has added
synthetic lysine. Consult feed company prior to feeding at 14 percent crude protein feed to foals or weanlings.
Foals with access to balanced feed still should be
observed carefully to make sure they do not sort, thus
consuming an unbalanced diet. Because foals tend to be
picky eaters, pelleted creep feeds will deal with sorting
problems better than will textured feeds. Such feeds will
not harm horses if the feeds are of top quality and pellets
are firm enough to force horses to chew them.
FeedingWeanlings
Many farms leave foals on mares longer than
necessary;12 although almost half of farms surveyed left
foals on mares for 6 months or longer, such delayed
weaning does not seem justified. Recent work showed no
difference in bone density or wither height between foals
weaned at 4-1/2 months and those weaned at 6 months.51
Research has shown that gradually weaned foals exhibit
less stress than do abruptly weaned foals.27 Whenever foals
are weaned, the transition likely will be smoother and
foals’ growth will be improved if they have been creep fed.
The weaned foal that will weigh 1,100 pounds at
maturity is expected to gain 1.5 to 2 pounds per day by 6
months of age. Total daily intake of hay and concentrate
usually will range from 2 to 3.0 percent of a horse’s body
weight. Higher levels of intake are difficult to achieve and
may overwhelm weanlings’ digestive capabilities.
At weaning, many horses are placed in confinement to
facilitate fitting programs. Young horses that are stalled and
given forced exercise need to be fed a balance of correct
nutrients to minimize joint disorders and to allow for
increased skeletal remodeling in response to work. Because
these young horses must lay down bone in support of
both growth and exercise, inadequate nutrient supply can
produce weak, fibrous bone rather than strong, dense bone.
Many horse owners favor giving weanlings an exclusive
diet of oats and alfalfa hay. While both of these are excellent
feedstuffs, a 70:30 ratio of oats to alfalfa hay provides
only 90 percent of the lysine and 80 percent of the calcium
needed by weanlings, relative to the caloric density (see
Table 5). Also, the commonly fed 50:50 diet of oats and
alfalfa provides even less of these required nutrients. Oats
and alfalfa hay may be fed as part of weanlings’ daily
diet, but supplemental nutrients are needed as well, to
help prevent swollen physes and joints and other skeletal
problems. One study found that horses eating only
oats and alfalfa got fatter, while those eating a balanced
concentrate along with alfalfa gained more height.14
Some Texas farms have tried to manage weanlings by
feeding concentrate:hay ratios more suited to yearlings.12
Weanlings cannot process hay or roughage as well as
yearlings; an oversupply of roughage relative to amount
of balanced concentrate feed is partially responsible for
the pot-bellied, scruffy appearance of some weanlings.
A feeding program containing roughly a 70:30 ratio of
concentrate to hay will help to achieve the gains and
skeletal development of which weanling horses are
capable.31
Young horses can be developed equally well using
either grass or legume roughage, but the type and quality
of hay or grazing available will influence the nutrient
concentration needed in a grain or concentrate mix.
Research has shown that high-quality alfalfa is more
digestible than grass hay, but good-quality grass hay is
more digestible than average-quality alfalfa.13 The added
“bloom” that some horse owners recognize when feeding
alfalfa is due to the additional energy in alfalfa compared
to many grass hays. This same appearance can be achieved
with grass hay as a roughage source by balancing the
grain mix based on the particular hay’s nutrient content.
Because of uncertainty as to whether protein in verygood-quality alfalfa interferes with calcium retention,
there is merit to feeding young horses a mixture of both
grass and alfalfa hays.
The ration shown in Table 4 was designed to be fed
with high-quality grass hay or with a mixture of grass and
alfalfa in a 70:30 grain-to-hay ratio.
Weanlings with access to good-quality alfalfa hay
generally need less protein and calcium in the concentrate
mix. However, the grain mix should always contain at least
as much calcium as phosphorus, with enough protein to
meet amino acid requirements. Although alfalfa contains
much more calcium and protein than do grass hays, some
calcium may be unavailable, and much of the protein is
not absorbed in the form of the amino acids needed for
growth.13,21
9
FeedingYearlings
As young horses become yearlings, necessary nutrient
concentrations in proportion to energy levels in feedstuffs
become lower but no less important. Yearlings not being
fitted for sales, futurities or early training can be developed
at a moderate rate of growth on all forage diets.19,42
Forage availability is as important as forage quality in
determining growth rates.1,52 Yearling horses can meet
the majority of their nutrient requirements for moderate
growth from forage because they graze 15 or more hours
per day on improved, high-quality pastures.
Yearlings being fitted or conditioned and receiving
forced exercise will require a combination of roughage
and concentrate, regardless of whether moderate or
rapid growth is desired. Yearlings receiving top-quality
grass hay or grazing can be fed a balanced ration such as
that shown in Table 6, at a 65:35 ratio of grain-to-hay. If
lower-quality hay is being fed (less than 7.5 percent crude
protein), a ration higher in protein and other nutrients is
required. Yearlings fed top-quality alfalfa hay (minimum
15 percent crude protein) will require a grain or concentrate
containing at least 12 percent crude protein. Since hay
quality varies, serious horse owners should take core
samples from their hay supply and have these cores
analyzed for nutrient content.
Forced exercise associated with fitting programs
increases yearlings’ needs for calcium, phosphorus and
magnesium. Recent research with long yearlings in
training has demonstrated a 35% increase in requirements
for calcium and phosphorus. It appears magnesium
requirements are about two times higher than previously
estimated.30,46. These mineral needs are best met by
feeding formulated horse feed rather than by trying to
supply individual minerals in addition to the feed.
Hay and grain intake varies according to the individual
horse and is influenced by exercise levels. Body condition
should be monitored routinely,16 and feed allowance should
be increased or decreased based on the horse’s appearance.
Remember that horses’ requirements are calculated based
on weight rather than on volume. Grain rations shown in
Tables 4 and 6 contain more energy than do plain oats,
with from 10 to 15 percent less concentrate normally
needed to achieve similar body condition. Table 7 shows
examples of minimum amounts of hay and concentrate to
be fed to meet an average horse’s requirements. Feed intake
should be increased gradually, making sure that hay intake
remains adequate. Note the differences in feed intake for
moderate growth versus feed intake for rapid growth.
Routine after-weaning management usually creates
an artificial environment of meal feedings. Foals are
accustomed to nursing 70 times per day early in life, then
typically end up in confinement or semi-confinement,
in a meal-feeding situation. While young horses most
commonly are fed twice daily, evidence suggests that
feeding three or four times in 24 hours actually may
improve nutrient absorption while decreasing surges
in glucose and insulin.11 For maximum success and
minimal digestive problems, feedings should be evenly
spaced, with equal time intervals between each feeding,
including from the last feeding of the day to the first
feeding of the next day.
Forced exercise should be conducted on footing that is not too deep.
RoleofExercise
When fed for rapid development, numerous evenly spaced feedings over
24 hours help promote growth.
FeedingManagementforBestResults
The very best formulated rations may not yield
desirable results simply because of how they are fed. Even
the most carefully balanced grain mix will be only as
effective as the feeding management program in which it is
used.
10
Exercise is vital in fostering growth and in
maintaining cartilage, bone quality and strength29.
However, epiphysitis, osteochondrosis (OCD) and some
expressions of “contracted tendons” may result from
nutrient imbalances in young horses receiving excessive
forced exercise in deep footing.
Obviously, horses being conditioned for shows or sales
must be kept in confinement and worked, but the manner
in which they are worked is very important. In one study
of young horses, exercise did not influence the number of
OCD lesions, but the most severe lesions were observed
in stall-rested horses.29 Although exercise is important,
Yearlings will grow at a moderate rate on improved pastures. Supplemental feeding will further improve body condition and gain.
forced exercise should include routine evaluation;
in most cases, young horses also will benefit from
free exercise. Intense, hard work should be introduced
gradually to encourage proper bone remodeling. Sudden
changes in stress cause the skeletal system to remodel
bone, but it takes time to develop needed strength. If at all
possible, conditioning programs should provide adequate
free exercise. Some conditioning programs alternate intense
work with free exercise and less-intense work on a weekly
basis to provide time for bone remodeling to occur. Well
over half of Texas farms surveyed reported using forced
exercise on an every-other-day basis12. Such schedules
are supported by research showing the importance of
providing adequate recovery time from skeletal strain.30
It is important to remember that the skeletal system
must be developed first, and the muscle system, later.
The skeletal system is best stimulated by very short work
periods on firm footing, followed by free exercise on soft
footing.4 Excessive forced or free exercise on firm footing
may cause trauma to the juvenile skeleton.
DoNotUseAnabolicSteroids
There has been a great deal of interest in anabolic
steroid use and its effect on the horse industry. Controlled
research trials have shown that growth rates have not
improved for horses injected with varying levels of
anabolic steroids.5 However, these studies observed altered
sexual behavior in treated horses.44,45
Injected stallions had decreased scrotal width, and
their testicular weight was 40 to 60 percent less than that
of untreated horses. Sperm motility and concentration and
total sperm per ejaculate all were lowered significantly by
steroid treatment. Injected mares had small, hard ovaries
typical of winter anestrous mares. These mares cycled less
regularly and often exhibited abnormal behavior, such as
mounting and teasing.
Anabolic steroids actually may cause premature closure
of the physes of long bones,24 resulting in cessation of
growth. These studies all suggest that use of anabolic
steroids for growth promotion is detrimental to young
horses.
BloodandHairAnalysis
Blood and hair analyses sometimes are used as
indicators of nutritional status. However, it should
be pointed out that, regardless of calcium in the diet,
blood calcium levels normally remain fairly constant
at the expense of calcium mobilization from the bone.26
Furthermore, hair analyses are of little or no value in
measuring calcium and phosphorus status and may not
be indicative of mineral deficiencies.9,53 Only proper ration
formulation and accurate feeding management reliably
indicate nutritional status.
Summary
Raising young horses that are sound and competitive
in today’s horse industry requires a carefully planned
feeding and management program. Some horses inherit
a propensity for skeletal defects, and such problems
may appear when these horses are fed for rapid early
development. In many cases, however, skeletal disorders
are the result of nutrient imbalances that precipitate
abnormal bone metabolism. When such nutrient
imbalances are paired with confinement and excessive,
forced exercise in deep footing, skeletal problems may
result. However, if horses are free from genetic defects,
there is no reason to expect that rapid early growth itself
will cause skeletal disease and lameness. Horse owners
who give time and care to the feeding of properly balanced
rations can expect to be more successful in growing young
horses. Careful feeding for moderate or rapid growth rates
can better ensure that such horses are sound at maturity.
11
Table 4. Creep feed and weanling ration (weanling ration designed to be fed with good-quality grass hay or grazing or a mixture of grass and alfalfa hay)
Ingredients
Percent
Pounds/ton
CalculatedAnalyses
40
800
Crude Protein=16.5%
32.5
650
Lysine=.80%
Soybeanmeal
20
400
Digestible
energy=1.39 Mcal/lb.
Molasses
5
100
Far=3.2% (no added fat)
Calciumcarbonate
1
20
Fiber=6%
Dicalciumphosphate
1
20
Calcium=.80%
0.5
10
Phosphorus=.50%
+
+
Vitamin A added at
1200 IUs/lb.
CrackedCorn
Oats
TraceMineralSalt
VitaminA
Table 5. Comparison of weanling requirements and nutrients provided per unit of energy for a weanling eating straight oats and alfalfa hay.
Nutrient:calorieratios(gramsofnutrientpermegacalorieofdigestibleenergy)
Nutrient
Providedbyoatsandalfalfahay
RequiredbyWeanling
51.0
50.0
Protein
Lysine
Threonine
Calcium
Phosphorus
1.8*
2.1
1.6
1.5
1.7*
2.1
1.2
1.2
*Lysine is less than required. Weanlings eating this diet are protein sufficient but deficient in the number one growth-limiting amino acid. Weanlings also
are deficient in calcium, unless larger amounts of alfalfa hay are fed. However, extra alfalfa will not correct the lysine deficiency.
Table 6. Yearling ration (to be fed with good quality hay)
Ingredients
Percent
Pounds/ton
47.5
950
Oats
30
600
CalculatedAnalysis
Soybeanmeal
15
300
Molasses
5
100
Calciumcarbonate
.5
10
Dicalciumphosphate
1.5
30
TMsalt
.5
10
VitaminA
+
+
C.P = 14.7%
Lysine = .66%
Dig. Energy = 1.42 mcal/lb
Calcium = .66%
Phosphorus = .63%
Vit A added at 1500 IU’s/lb
Crackedcorn
*Important: Read section on use of feedstuffs and potential problems.
12
Table 7. Examples of various daily feeding amounts for young horses being fed rations shown in Tables 5 and 7* (1,100-pound mature weight)
Alfalfahay
(pounds)
Pounds14%
mix**
(Table7)
Moderategrowth
3.75
8.75
12.5
Rapidgrowth
4.00
10.00
14.0
Age
Grasshay
(pounds)
Pounds16%
mix
(Table5)
Totalfeed
(pounds)
Weanlings
Moderategrowth
3.75
8.75
12.5
Rapidgrowth
4.00
10.00
14.0
Yearlings
Moderategrowth
10.00
7.00
17.0
Rapidgrowth
11.25
7.25
18.5
•CombinationsofhayandgrainshownrepresentMINIMUMamountstomeetrequirements.Adjustintake
graduallyaccordingtodesiredbodyconditionandbasedonindividualvariabilityandexercise.Horses
shouldbefedatleasttwicedaily.Dividingtotalamountsshownintoatleasttwoequalfeedingswill
minimizedigestivedisorders.
•**Donotfeeda14%crudeproteinfeedtoweanlingsunlessthatfeedcontainsatleast.7%lysine.If
lysinecontentisnotshownonthetagorthebag,contactthefeedmanufacturertodeterminelysine
concentration.
13
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16
31. NRC, 1989. Nutrient Requirements of Horses. National Academy of Sciences.
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17
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18
ProtectYourYoungHorses
HorseTheftAwarenessandPrevention
• Consider permanent identification with brands, microchips or lip tattoos.
• Record permanent marks or brands with the county clerk in the county
where the horses live.
• Keep on hand current photographs or video footage of weanlings, yearlings
and two-year-olds. Be sure photos or video include any unique marks,
brands, color patterns or other distinguishing characteristics.
• Establish an organized proof-of-ownership file with photos, registration
information, health papers and any other supporting information.
• Secure barns, corrals or pens from the road with a good perimeter fence.
• Use well-built gates that cannot be lifted off the hinges and that can be locked.
• Feed pastured horses well away from the gate or road, because horses will
congregate around feeding areas and be easier to catch.
• Check on pastured horses regularly. Keep up activity levels and consider
establishing a horse/facilities watch program with others in your area.
• Do not leave halters on pastured horses, particularly young, growing horses.
• Do not leave halters hanging where they can be used by somebody else, and
lock up expensive tack.
• Secure hitches on horse trailers or hide trailers from public view, making them
harder to see and even harder to steal.
• Post warning signs on pasture gates and fences where appropriate.
Contact Texas Cooperative Extension for the following information on horse
theft awareness and prevention:
L-5210 – Fifteen steps to minimize theft of horses and equipment
L-5211 – Permanent identification of horses
L-5244 – What to do if your horse is stolen
Video Tape – Horse Theft Protection
All printed and video material related to horse theft awareness is free to horse
owners in Texas. Contact your local county Extension office, or the Extension
Horse Specialists, Kleberg 249, TAMU 2471, College Station, Texas 77843. Printed
material also is available at http://aminalscience.tamu.edu
The information given herein is for educational purposes only. Reference to commercial products or trade names is made
with the understanding that no discrimination is intended and no endorsement by Texas Cooperative Extension is implied.
Produced by Agricultural Communications, The Texas A&M University System
Extension publications can be found on the Web at: http://tcebookstore.org
Visit Texas Cooperative Extension at http://texasextension.tamu.edu
Educational programs conducted by Texas Cooperative Extension serve people of all ages regardless of socioeconomic level, race, color, sex, religion,
handicap or national origin.
Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as amended, and June 30,
1914, in cooperation with the United States Department of Agriculture. Edward G. Smith, Director, Texas Cooperative Extension, The Texas A&M University
System.
12M, New